Endless check straps



Dec. 19, 1967 Q ME$sER 3,358,716

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United States Patent 3,358,716 ENDLESS CHECK STRAPS Chester R. Messer, Concord, NH, assignor to Page Belting Company, Concord, NH, a corporation of New Hampshire Filed Mar. 14, 1966, Ser. No. 533,895 7 Claims. (Cl. 139-161) ABSTRACT OF THE DISCLOSURE The invention comprises a check strap loop embodying inner and outer plies of textile material spliced in different opposed areas located respectively in the sides of the loop in combination with friction fingers arranged to bend inwardly the bonded area of the outer ply and the unbroken area of the inner ply.

This invention comprises a new and improved check strap of the type characterized by an endless elongated loop which is arranged to slide between frictional fingers under the actuation of an oscillating picker stick which is confined and limited in its stroke by the loop.

Check straps of this type are subjected to very severe duty and for many years the textile industry has devoted extensive research and effort to increasing the life of the strap. Every advance in that direction is of great importance as it permits the employment of looms operating at increased speed and with reduced down time. A gain in speed of only a few picks per minute may make the difference between profit and loss to the manufacturer. It has been found, however, that every increase in loom speed magnifies the severity of duty, reduces the life of the check strap assembly and must be offset by effective improvement in the check strap itself to meet the manufacturers demand for faster operation.

I have discovered structural and functional improvements which are effective to increase the life and efiiciency of such check strap assemblies and are therefore of outstanding importance and unexpected benefit to the textile industry.

The improved check strap of my invention comprises two or more laminated plies of textile fabric superposed in elongated loop formation and being spliced respectively in opposed areas in the sides of the loop, bonded together throughout their length and impregnated with a thermosetting compound in at least some portions of the ides of the loop.

The strap is installed in the loom in association with adjustable friction fingers which engage one side of the loop and impart to it a sinuous path of inward convexity. The outer ply of the loop is spliced in this area with the result of eliminating tension which would tend to open and impair the splice in this ply. Tension in the loop is carried at this point by the unspliced inner ply.

On the other hand the other side of the loop is guided in a substantially straight path where the inner ply is subjected to a little or no bending tension and the outer unspliced ply is in position to carry the full working load.

The construction above described has the advantage that no free ends of textile plies are exposed at any time in the service life of the strap to direct impact of the picker stick so there is no point in the loop in which unraveling occurs. Moreover, the strap provides a multiplicity of unbroken plies in the area of picker contact at least in the power stroke of the picker stick, a feature which prolongs the service life of the strap.

The strength and life of the strap is also increased by providing it with a series of spaced longitudinal lines of stitching. This constitutes an additional bond between the components of the strap and positively prevents any migrating progress of one ply with respect to another in long continued operation.

My improved check strap has the further advantage that it may 'be used alone or in association with a secondary external strap of the general type shown in United States Letters Patent 2,796,086, June 18, 1957, Moon et a1.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings in which:

FIG. 1 is a plan view of the composite check strap,

FIG. 2 is a view in elevation,

FIG. 3 is a plan view showing a composite strap of modified construction, and

FIG. 4 is a fragmentary view showing a modified form of loop end structure.

The inner and outer straps of the composite loop are preferably close woven from coarse strands of nylon or other synthetic thermoplastic fabric.

The outer strip 10 may be approximately two inches in width and one-eighth inch in thickness and is spliced about midway in the outer long side of the loop at 11 where the ends of the strap are butted and fused together.

The inner strap 12 is of similar construction, spliced at a point about midway in the inner wall of the elongated loop at 13 and of such dimensions as to fit snugly within the loop of the outer strap. The assembled straps 10 and 12 are bound together by endless lines of stitching 14 passing through both straps and evenly spaced throughout their width.

A set of friction fingers 15 is arranged to engage one side of the loop and to impart to it a sinuous path of inward convexity thereby causing frictional drag on the loop as it is moved back and forth by action of the picker stick 19. It will be seen that the splice 11 in the outer strap is located within range of the friction fingers at a point where bending tension is carried by the unspliced area of the inner ply. There is little or no tendency therefore to disturb the splice 11.

At its other side the loop passes between friction fingers 16 and a guide 17 without appreciable deflection and here the inner ply is spliced at 13 while the outer ply is of unbroken weave. It will be understood that the friction fingers 15 and 16 are transversely adjustable for controlling or equalizing the drag on the loop as a whole.

The loop of FIG. 3 is fashioned from a single strap coiled to present double thickness at the working end of the picker stick stroke. The strap is coiled to bring its two ends 20 and 21 toward the single ply end of the elongated loop, that is to say, the left hand end as seen in FIG. 3. The end 20 falls within the loop and the end 21 lies outside it. The overlapping portions of the strap are united by fusion and also by lines of stitching like those of FIG. 2.

The loops of FIGS. 2 and 3 are impregnated with polyurethane or other thermosetting resin in an intermediate area 18 on each side where the loop travels in contact with the friction fingers. The effect of this impregnation is to strengthen the loop and guard against the formation of ripples therein. The impregnated areas 18 taper at both ends in order to avoid concentrating their effect at an abrupt line of division. The final shape is given to the assembled and stitched straps by enclosing them for a short period under heat and pressure in a mold of the desired shape.

A modified form of loop end is shown in FIG. 4 where the upper portions 22 of the straps are pinched together and molded in V-formation while the lower portions 23 remain in the shape of an arc which is tangent to the straighter sides of the loop. The effect of thi molding treatment is to increase the contact area of the loop with the picker stick by disposing the inner end surface of the loop at substantially the same angle as that reached by the picker stick at the end of its stroke.

Having thus disclosed my invention what I claim as new and desire to secure by Letters Patent is:

1. A check strap assembly comprising the combination of an endless textile strap and friction fingers, the strap having inner and outer plies laminated together in elongated loop formation and spliced respectively in different areas located respectively in the long sides of the loop formation, the plies being bonded together throughout their length, and the friction fingers being arranged to bend inwardly the spliced area of the outer ply and the unspliced area of the inner ply.

2. An endless check strap as defined in claim 1, further characterized in that the splice in an inner ply of the strap is located in an area subject to guidance in a straight path and the splice in an outer ply is located in an area subject to inward deflection of the loop in service.

3. An endless check strap as defined in claim 1, further characterized in that the two plies are united throughout their areas of contact by cured polyurethane.

4. An endless check strap as defined in claim 1, further characterized in that each ply is formed of nylon fabric and made endless by fusion of nylon at butted ends in the sides of the loop.

5. An endless check strap as defined in claim 1, further characterized in that the laminated plies are bound together by spaced longitudinal lines of stitching.

6. An endless check strap as defined in claim 1, further characterized in that the upper end portions of the loop as it surrounds the picker stick are pinched together and molded in V-formation while the lower end portions are in the shape of an are which is tangent at its ends to the straighter sides of the loop.

7. An endless check strap comprising a single length of synthetic fabric coiled to present an elongated loop of double thickness at the working end of the picker stick stroke and single thickness of greater flexibility at its other end of the loop, both ends of the strap being located near the single ply end of the loop and united by fusion and by lines of stitching.

References Cited UNITED STATES PATENTS 3,288,174- 11/1966 Messer 13916l 2,291,587 7/1942 Howarth l39161 2,533,646 12/1950 Wakefield 139-461 X 2,741,273 4/1956 Robert 139-161 2,822,828 2/1958 Crocker 139161 3,060,547 10/1962 Macbean 139-383 X 3,228,429 1/1966 Messer 139161 3,282,302 11/1966 Messer 139-161 2,374,042 4/1945 Shivell 139165 MERVIN STEIN, Primary Examiner.

J. KEE CHI, Assistant Examiner. 

1. A CHECK STRAP ASSEMBLY COMPRISING THE COMBINATION OF AN ENDLESS TEXTILE STRAP AND FRICTION FINGERS, THE STRAP HAVING INNER AND OUTER PLIES LAMINATED TOGETHER IN ELONGATED LOOP FORMATION AND SPLICED RESPECTIVELY IN DIFFERENT AREAS LOCATED RESPECTIVELY IN THE LONG SIDES OF THE LOOP FORMATION, THE PLIES BEING BONDED TOGETHER THROUGHOUT THEIR LENGTH, AND THE FRICTION FINGERS BEING ARRANGED TO BEND INWARDLY THE SPLICED AREA OF THE OUTER PLY AND THE UNSPLICED AREA OF THE INNER PLY. 